JP2009253468A - Video controller and method of controlling the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stably perform input switching from a plurality of devices to be subjected to authentication processing. <P>SOLUTION: When DDC access is requested from an external connection device connected to an HDMI port, a television receiver sets an HPD signal to a High state to set the DDC access ON. When a request to start authentication using HDCP is received from the external connection device after transmission of EDID upon receiving the request from the external connection device, it is determined whether an HDMI port to which the corresponding external connection device is connected is selected from a plurality of HDMI ports. When it is determined that the corresponding port is not selected, selection of the HDMI port to which the corresponding external connection device is connected is put on standby. When the corresponding port is selected, the HPD signal is set to a Low state to set the DDC access OFF. Then, after 100 msec have elapsed, the HPD signal is switched to the High state to set again the DDC access ON. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a video control device and a video control method, and more particularly to a video control device including a plurality of connection terminals to which externally connected devices that transmit video data and audio data are connected, and a control method therefor.

  In recent years, resolution of video signals input to video control devices such as television receivers has been increasing. For example, in terrestrial digital broadcasting, an image of 1920 pixels × 1080 pixels called a full high-definition image is often used. Such a high-resolution video signal has an enormous amount of information transmitted per unit time. Therefore, an interface called HDMI is used to transmit the high-resolution video signal from an externally connected device such as a hard disk recorder to the television receiver. HDMI is an abbreviation for High-Definition Multimedia Interface.

  HDMI has the advantage that video data and audio data can be transmitted with a single cable, and there is no hassle of connecting multiple cables. For this reason, the number of HDMI port video control devices that are connected by HDMI is increasing year by year.

  In HDMI, information transmission is performed between connected devices using a TMDS channel, a CEC channel, and a DDC. A TMDS (Transition Minimized Differential Signaling) channel transmits video data, audio data, and auxiliary data.

  A CEC (Consumer Electronics Control) channel transmits device control signals. By using communication using the CEC channel (hereinafter referred to as CEC communication), the video control device and the externally connected device connected by HDMI are controlled in conjunction with one remote controller instead of each remote controller. It becomes possible. For example, functions such as turning off the power of the externally connected device in conjunction with the power off of the video control device or executing input switching of the video control device in conjunction with the start of playback of the externally connected device can be realized.

  In HDMI, EDID is transmitted by DDC and authentication by HDCP is performed. Note that DDC is an abbreviation for Display Data Channel. EDID is an abbreviation for Extended Display Identification Data. HDCP is an abbreviation for High-bandwidth Digital Content Protection.

  Various information such as information on the video control device and a source physical address (hereinafter, “physical address”) is transmitted by EDID. The physical address indicates the address of a device connected to the HDMI port. That is, by using EDID, it is possible to notify the resolution that can be received by the video control device, the audio stream information, the speaker information that the video control device has, and the physical address that the external device should acquire.

  According to HDCP, video data and audio data transmitted from an external device to the video control apparatus are encrypted using a public key method. In HDMI, authentication by HDCP is performed by performing communication via an HDMI cable. As a result, for example, when the externally connected device does not authenticate the video control device, the externally connected device rejects transmission of video data and audio data to the video control device.

Patent Document 1 describes a technology related to communication by DDC. The DDC communication is started by turning on an HDMI HPD (Hot Plug Detect) signal from OFF to ON on the video control device side. According to Patent Document 1, when the video data and audio data transmitted from the external device side according to the DDC communication are different from the format set on the video control device side, the HPD signal is turned off again on the video control device side. By turning on, DDC communication is performed again. Thereby, it is solved that video and audio are not output when DDC communication fails.
JP 2007-78980 A

  Here, consider a case where input switching of a video control apparatus is performed using the CEC function in an environment in which a plurality of externally connected devices are connected to one video control apparatus by HDMI. In this case, when performing input switching by the CEC function, it is necessary to transmit an EDID from the video control device to each external connection device in advance and generate a physical address of each external connection device. For this reason, the video control apparatus needs to mount an EDID ROM in which EDID information is stored in each HDMI port.

  On the other hand, the video control apparatus holds authentication information for performing authentication by HDCP in the ROM for HDCP. This authentication information is required for authentication for decrypting the video data and audio data transmitted from the external device to the video control apparatus. Therefore, the video control apparatus only needs to have the HDCP ROM corresponding to the number of HDMI ports that can be simultaneously displayed on one screen.

  That is, while the EDID ROM is mounted on each HDMI port, the HDCP ROM may be mounted in a smaller number than the HDMI port number of the video control device.

  If the number of HDCP ROMs is smaller than the number of EDID ROMs in this way, the externally connected device can access the EDID ROM when DDC communication is performed between the externally connected device and the video control device. Therefore, the HDCP ROM cannot be accessed. In this case, a response to the access request for the HDCP ROM cannot be obtained, and the state of the DDC line becomes indefinite. When input switching is performed in the video control device when the DDC line is in an indefinite state, there is a problem that access by the DDC does not return normally, and video data display or audio data output may not be possible. .

  For example, in the externally connected device selected by the input switching, if the HDCP ROM cannot be accessed and the video control device cannot be authenticated by HDCP, transmission of video data and audio data is rejected in the externally connected device. . In addition, for example, there may be a case where the externally connected device cannot normally return from the waiting state for an access response to the HDCP ROM.

  In the above-described Patent Document 1, a receiver monitors video data and audio data received, and determines whether or not video data and audio data in a format that can be handled by the receiver are received. When it is determined that video data and audio data in a format that cannot be output by the receiver is received, the data is recognized as abnormal data. When reception of abnormal data is recognized, the HPD signal is turned off, and then the HPD signal is turned on again to start DDC access again.

  However, the technique disclosed in Patent Document 1 has a problem that a circuit unit for monitoring video data and audio data is required. In Patent Document 1, it is necessary to detect the format of these received data in order to determine whether the received video data or audio data is abnormal data. For this reason, there is a problem that a certain time is required until the received video data and audio data are recognized as abnormal data.

  Therefore, an object of the present invention is to provide a video control apparatus and a control method therefor that can stably perform input switching from a plurality of devices that require authentication processing.

  In order to solve the above-described problems, the present invention provides a plurality of connection means for connecting externally connected devices, and each of the plurality of connection means starts communication initialization processing for the externally connected device. A control signal line for notifying, selecting means for selecting at least one of video data and audio data among a plurality of connecting means, and an externally connected device including video data and audio data. Authentication information necessary for communication for outputting at least one is stored, and can be accessed from an externally connected device connected to the connection means selected by the selection means, and a control signal line included in the connection means Notification for notifying externally connected devices connected to the connection means to start communication initialization processing including access to the storage means A control signal line included in the connection means newly selected by the change when the change of the connection means selected by the selection means is detected. The video control apparatus is characterized in that the notification means is controlled so as to perform the notification.

  The present invention also provides video data and audio data among a plurality of connection means each including a control signal line for notifying the externally connected device of the start of communication initialization processing for connecting the externally connected device. A selection step of selecting one of at least one of the input destinations, and authentication information required for communication for the external device to output at least one of video data and audio data is stored and selected by the selection step The communication initialization process including access to the storage means accessible from the externally connected device connected to the connecting means is applied to the externally connected equipment connected to the connecting means by the control signal line included in the connecting means. And a control step for controlling notification by the notification step. When the change of the connection means selected by the selection step is detected, the video control is characterized in that the notification step is controlled so as to be notified by the control signal line included in the connection means newly selected by the change. This is a method for controlling the apparatus.

  Since the present invention has the above-described configuration, it is possible to stably perform input switching from a plurality of devices that require authentication processing.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 schematically shows a system configuration of an example to which the present invention can be applied. A television receiver 100 as a video control apparatus has a plurality of HDMI terminals. In the example of FIG. 1, the television receiver 100 has two HDMI ports 103 and 104 and can connect up to two external connection devices corresponding to HDMI.

  Here, it is assumed that the external connection device 101 is connected to the HDMI port 103 via the HDMI cable 210A. Further, it is assumed that the external connection device 102 is connected to the HDMI port 104 via the HDMI cable 210B. Assume that the externally connected devices 101 and 102 are recorders that record and reproduce video data and audio data using a recording medium such as a hard disk or an optical disk.

  The television receiver 100 can be operated remotely by a remote control commander 200 (hereinafter abbreviated as a remote controller 200). For example, the remote controller 200 modulates a control signal generated in response to an operation on the operation unit into an infrared signal and transmits the infrared signal. This infrared signal is received by the infrared receiver 201 of the television receiver 100 and demodulated to restore the control signal. A control unit (not shown) of the television receiver 100 controls each unit of the television receiver 100 based on this control signal, and realizes an operation according to an operation performed on the remote controller 200.

  For example, the television receiver 100 can select one of the HDMI ports 103 and 104 as an external input terminal in accordance with an operation on the remote controller 200. A video based on video data output from a device connected to the selected HDMI port (referred to as the external connection device 101) is displayed on the display unit 202 such as an LCD (Liquid Crystal Display).

  Assume that the user operates the remote controller 200 and inputs an instruction to switch the external input terminal from the HDMI port 103 to the HDMI port 104. As a result, a control unit (not shown) controls a selector 107, which will be described later, so as to select the HDMI port 104. As a result, the selected device is switched from the external device 101 to the external device 102. Then, the display on the display unit 202 is switched from video based on video data output from the externally connected device 101 to video based on video data output from the externally connected device 102.

  In addition, the operation of the device connected to the television receiver 100 via HDMI can be controlled by operating the remote controller 200. In the example of FIG. 1, a recording / reproducing operation or the like in the external connection device 101 or the external connection device 102 can be controlled by an operation on the remote controller 200.

  FIG. 2 is a block diagram illustrating a configuration example of the television receiver 100. The CPU 220 is connected to a ROM and a RAM (not shown), and controls the overall operation of the television receiver 100 using the RAM as a work memory in accordance with a program stored in the ROM. For example, the CPU 220 transmits various commands and control signals for controlling the television receiver 100 based on a control signal that is transmitted from the remote controller 200 in response to a user operation and received by the infrared light receiver 201 and demodulated. Is generated and output.

  A selector 107 serving as a selection unit switches the selection input terminals 107A and 107B in accordance with a selector switching signal 114 supplied from the CPU 220. Accordingly, the selector 107 selects one of the HDMI port 103 and the HDMI port 104 as an input destination of video data and audio data. For example, the CPU 220 generates the selector switching signal 114 in response to a user operation on the remote controller 200. The selector switching signal 114 is supplied to the selector 107 and also to the control unit 112.

  The HDMI receiver 108 receives a signal input from the HDMI port selected from the HDMI ports 103 and 104 by the selector 107. Of the signals received by the HDMI receiver 108, video data is supplied to the video processing unit 110, and is subjected to display on the display unit 202 after predetermined signal processing is applied. Similarly, audio data data among signals received by the HDMI receiver 108 is supplied to the audio processing unit 111, and after predetermined signal processing is applied, is output as audio by an acoustic device such as a speaker (not shown).

  The HDMI ports 103 and 104 as connection means have TMDS lines # 1 and # 2, 5V Power lines 116 and 117, and DDC lines 122 and 123, respectively. Further, the HDMI ports 103 and 104 have HPD lines 119 and 120 as control signal lines. Although not shown, the HDMI ports 103 and 104 further include a CEC line for transmitting and receiving a CEC command for interlocking operation between the television receiver 100 and the external connection devices 101 and 102. .

  The control unit 112 as a control unit includes a selector determination unit 113, a 5 VPower determination unit 115, an HPD transmission unit 118, an EDID final determination unit 121, and an HDCP start determination unit 124. Each of the determination unit and the transmission unit included in the control unit 112 is controlled by, for example, a CPU (not shown) and a program stored in advance in a ROM (not shown).

  The TMDS lines # 1 and # 2 are lines for transmitting video data, audio data, and auxiliary data from the external connection devices 101 and 102 to the television receiver 100. The DDC lines 122 and 123 are lines for exchanging EDID and transferring authentication information by HDCP between the television receiver 100 and the externally connected devices 101 and 102. That is, the DDC lines 122 and 123 are shared by EDID transmission and HDCP encryption authentication delivery.

  The TMDS line # 1 and the DDC line 122 derived from the HDMI port 103 are connected to the selection input terminal 107A of the selector 107. The DDC line 122 is connected to the control unit 112 while being connected to the EDID ROM 105. The DDC line 122 connected to the control unit 112 is branched in the control unit 112 and connected to the EDID final determination unit 121 and the HDCP start determination unit 124, respectively.

  Similarly, TMDS line # 2 and DDC line 123 derived from the HDMI port 104 are connected to the selection input terminal 107B of the selector 107. The DDC line 123 is connected to the control unit 112 as well as to the EDID ROM 105. As illustrated, the DDC line 123 is branched in the control unit 112 and connected to the EDID final determination unit 121 and the HDCP start determination unit 124, respectively.

  The EDID final determination unit 121 detects final EDID access data from the EDID transmitted via the DDC lines 122 and 123. The HDCP start determination unit 124 detects HDCP access start data (referred to as a key selection vector) supplied via the DDC lines 122 and 123.

  The EDID ROMs 105 and 106 as device information storage means are rewritable nonvolatile memories. The EDID ROMs 105 and 106 store various information related to the television receiver 100 such as display performance, HDMI port address information such as a physical address, and the like. The EDID ROMs 105 and 106 store individual physical addresses for the HDMI ports 103 and 104, respectively. For example, the physical address [1.0.0.0] is stored in the EDID ROM 105, and the physical address [2.0.0.0] is stored in the EDID ROM 106.

  5V Power lines 116 and 117 derived from the HDMI ports 103 and 104 are connected to a 5V Power determination unit 115 in the control unit 112, respectively. The 5V Power lines 116 and 117 are lines for requesting DDC access from the external connection devices 101 and 102 to the television receiver 100, respectively.

  HPD lines 119 and 120 derived from the HDMI ports 103 and 104 are connected to the HPD transmission unit 118 in the control unit 112, respectively. The HPD lines 119 and 120 are lines for notifying that the preparation for DDC access is completed from the television receiver 100 to the externally connected devices 101 and 102, respectively. The HPD transmission unit 118 serving as a notification unit causes the potentials of the HPD lines 119 and 120 to be in a high voltage high state (on level) or a low voltage low state (off level). In the High state, the DHDMI access preparation is completed in the corresponding HDMI port and the DDC access is turned on. When the HPD lines 119 and 120 are in the low state, the DDC access is turned off. According to HDMI, the voltage in the high state is in the range of 2.4V to 5.3V, and the voltage in the low state is in the range of 0V to 0.4V.

  An HDCP ROM 109 as a storage means is connected to the HDMI receiver 108. The HDCP ROM 109 stores authentication information for performing HDCP authentication. Of the externally connected devices 101 and 102, a device connected to the HDMI port selected by the selector 107 can access the HDCP ROM 109. Of the externally connected devices 101 and 102, an HDCP authentication process is performed between the externally connected device that has accessed the HDCP ROM 109 and the television receiver 100. When the authentication process is successful, the HDMI receiver 108 decrypts the video data and audio data supplied from the selector 107.

  In the control unit 112, the selector determination unit 113 determines which of the selection input terminals 107 </ b> A and 107 </ b> B has been switched based on the selector switching signal 114 supplied from the CPU 220. Based on the determination result, the control unit 112 can detect which of the HDMI ports 103 and 104 is selected by the selector 107.

<First Embodiment>
Next, processing according to the first embodiment of the present invention will be described with reference to the flowchart of FIG. 3, the timing chart of FIG. 4, and the block diagram of FIG. 2 described above. FIG. 3 is a flowchart showing an example of processing according to the first embodiment of the present invention. Here, a case where the external connection device 102 is selected from the external connection device 101 connected to the HDMI port 103 and the external connection device 102 connected to the HDMI port 104 will be described as an example. Of course, the processing described below is the same even if the externally connected device 102 and the externally connected device 101 are interchanged.

  In step S <b> 1, the control unit 112 waits for a DDC access request from the external device 102. In the control unit 112, the 5V Power determination unit 115 determines the presence / absence of a DDC access request based on the voltage value of the 5V Power line 117 derived from the HDMI port 104 to which the external device 102 is connected. If it is determined that there is a DDC access request from the external device 102, the process proceeds to step S2.

  In step S2, the HPD transmission unit 118 transmits a High state HPD signal to the HPD line 120 to notify the externally connected device 102 that the DDC access has been turned on. As a result, the external connection device 102 is notified to start the communication initialization process.

  In the next step S3, an EDID request from the external device 102 is waited. When a slave address and a read command are supplied from the external device 102 to the EDID ROM 106 via the DDC line 123, the EDID is read from the EDID ROM 106 and transmitted to the external device 102 (step S4). ). This EDID is received by the external connection device 102.

  When the external connection device 102 determines that the reception of the EDID is completed, the external connection device 102 transmits a key selection vector to the television receiver 100 via the DDC line 123. When this key selection vector is received by the television receiver 100, it is supplied to the HDCP start determination unit 124 in the control unit 112 (step S5). The key selection vector is a command indicating the start of access by HDCP.

  The externally connected device 102 generates its own physical address based on the physical address of the HDMI port 104 stored in the received EDID. The generated physical address is transmitted from the external device 102 to the television receiver 100 by a CEC command at a predetermined timing, for example, during the processing from step S4 to step S5. This physical address is once written in the memory in the CPU 220. The television receiver 100 can control the externally connected device 102 with a CEC command using the physical address of the externally connected device 102.

  When the key selection vector is received by the HDCP start determination unit 124, the process proceeds to step S6. In step S6, the selector determination unit 113 determines which one of the selection input terminals 107A and 107B is selected in the selector 107. The selector determination unit 113 performs this determination based on, for example, the voltage value of the selector switching signal 114 or serial communication performed with the selector 107. Then, based on the determination result, the HDMI port selected by the selector 107 is detected, and of the HDMI ports 103 and 104, the port corresponding to the external connection device 102 (in this example, the HDMI port 104) is selected. It is determined whether or not.

  In step S6, if the selector 107 detects that the HDMI port 104 is selected based on the determination result of the selector determination unit 113, an authentication process based on HDCP is performed. That is, the external connection device 102 accesses the HDCP ROM 109 connected to the HDMI receiver 108 via the DDC line 123 and the selection input terminal 107B of the selector 107. Then, the external connection device 102 reads the authentication information stored in the HDCP ROM 109 via the DDC line 123 and authenticates the television receiver 100.

  If the authentication by HDCP is successful (step S7), it is determined that the communication initialization process is completed, and the process proceeds to step S8. Here, when the HDCP authentication in step S7 is successful, the externally connected device 102 outputs video data and audio data, and transmits them to the television receiver 100 via the HDMI cable 210B. In step S8, the television receiver 100 receives the video data and audio data via the HDMI port 104 (step S8), and supplies the data to the HDMI receiver 108 via the selection input terminal 107B of the selector 107. The HDMI receiver 108 decrypts the supplied video data and audio data, supplies the video data to the video processing unit 110, and supplies the audio data to the audio processing unit 111 (step S9).

  On the other hand, if it is determined in step S6 described above that the selector 107 does not select the HDMI port 104, the process proceeds to step S10, and it is determined that the HDCP authentication has failed. That is, if the HDMI port 103 is selected in the selector 107, the external connection device 102 cannot access the HDCP ROM 109. For this reason, the external connection device 102 cannot authenticate the television receiver 100 by HDCP, and the authentication fails.

  In the next step S11, the selector 107 waits for the HDMI port 104 corresponding to the external device 102 to be selected. For example, in step S11, the HDMI port selected by the selector 107 is detected based on the determination result of the selector determination unit 113. As a result, if it is determined that the selection is changed from the HDMI port 103 to the HDMI port 104, the process proceeds to step S12.

  If the HDCP authentication fails because the HDCP ROM 109 cannot be accessed from the external device 102 in step S10 described above, the DDC line 123 becomes indeterminate. In this case, even if the selector 107 selects the HDMI port 104 corresponding to the external connection device 102 after that, the external connection device 102 may not be able to transmit normal video data and audio data.

  Therefore, in the first embodiment, in step S12, the HPD transmission unit 118 transmits the HPD signal in the low state to the external connection device 102 for a predetermined time. The time for transmitting the HPD signal in the Low state is a time in which the external device 102 can recognize the Low state. According to the HDMI standard, this time is a minimum of 100 ms. Also in the first embodiment, in step S12, a Low state HPD signal is transmitted for 100 msec. Note that the transmission time of the Low state HPD signal is not limited to 100 msec, and may be longer than this time.

  When the transmission of the HPD signal in step S <b> 12 is completed, the process returns to step S <b> 2, and the HPD transmission unit 118 transmits the High state HPD signal to the external connection device 102. As a result, the external connection device 102 is notified again that the DDC access preparation is completed, the communication initialization process is executed again, and the EDID request process and the HDCP authentication process are performed.

  The process according to the first embodiment will be described more specifically with reference to the flowchart of FIG. 3 as appropriate while using the timing chart of FIG. 4A to 4D show examples of timings of various signals on the external device 101 side, that is, the HDMI port 103 side. 4F to 4I show examples of various signal timings on the external device 102 side, that is, the HDMI port 104 side. Further, FIG. 4E shows an example of operation timing of the selector 107. In FIG. 4E, the HDMI port 103 and the HDMI port 104 are shown as HDMI # 1 and HDMI # 2, respectively.

  More specifically, FIGS. 4 (a) and 4 (f) show examples of voltage changes on 5V Power lines 116 and 117, respectively. FIGS. 4B and 4G show examples of voltage changes on the HPD lines 119 and 120, respectively. FIG. 4C and FIG. 4H show examples of the state of DDC access, respectively. 4 (d) and 4 (i) show examples of video data and audio data output from the selector 107, respectively.

  As an example, a case where the external connection device 101 is connected to the HDMI port 103 from the beginning and the HDMI port 103 is selected in the selector 107 will be described. In this case, for example, a predetermined voltage is applied to the 5V Power line 116 with the activation of the external device 101 (time t1 in FIG. 4). The 5V Power determination unit 115 determines that there is a DDC access request from the external device 101 based on the voltage value of the 5V Power line 116 (step S1 in FIG. 3).

  In response to the DDC access request, the HPD transmitter 118 sets the HPD signal to the High state at time t2 (step S2 in FIG. 3). At a subsequent time t3, an access request for the EDID ROM 105 is transmitted from the external device 101 to the television receiver 100. Then, the EDID read from the EDID ROM 105 by this access request is transmitted to the external device 101 at time t3 (steps S3 and S4 in FIG. 3). When the external connection device 101 completes the reading of the EDID, the external connection device 101 transmits an HDCP key selection vector to the television receiver 100. This key selection vector is received by the HDCP start determination unit 124, and authentication by HDCP is attempted at time t4.

  At the time t4, the external device 101 is connected to the HDMI port 103, and the HDMI port 103 is selected by the selector 107 as illustrated in FIG. 4E (step S6 in FIG. 3). ). Therefore, the externally connected device 101 can access the HDCP ROM 109, and the HDCP authentication is successful (step S7 in FIG. 3). Thus, at time t5, video data and audio data are output from the external device 101 to the television receiver 100 (step S8 in FIG. 3).

  As another example, a case where the input is switched to the HDMI port 104 to which the external connection device 102 is connected in a state where the HDMI port 103 to which the external connection device 101 is connected is selected as an input as in the above-described example will be described. To do.

  For example, when a predetermined voltage is applied to the 5VPower line 117 with the activation of the externally connected device 102 (time t10 in FIG. 4), the 5VPower determining unit 115 determines that there is a DDC access request from the externally connected device 102. (Step S1 in FIG. 3).

  In response to the DDC access request, the HPD signal is set to a high state at time t11 (step S2 in FIG. 3), and thereafter, an access request to the EDID ROM 106 is transmitted from the external device 102 to the television receiver 100. . The EDID read from the EDID ROM 106 by this access request is transmitted to the external device 102 at time t12 (steps S3 and S4 in FIG. 3). When the external connection device 102 completes the reading of the EDID, the external connection device 102 transmits an HDCP key selection vector to the television receiver 100. This key selection vector is received by the HDCP start determination unit 124, and authentication by HDCP is attempted at time t13.

  As illustrated in FIG. 4E, the HDMI port 103 is selected in the selector 107 at time t13. Therefore, in step S6 in FIG. 3, it is determined that the HDMI port 104 corresponding to the externally connected device 102 has not been selected by the selector 107, the processing is shifted to step S10 in FIG. 3, and authentication by HDCP has failed. (Time t14). That is, at the time t14, the externally connected device 102 can access the EDID ROM 106 and cannot access the HDCP ROM 109, and the state of the DDC line 123 becomes indefinite.

  Thereafter, for example, it is assumed that the selected HDMI port 104 is selected at time t15 in the selector 107 in accordance with a user operation (step S11 in FIG. 3). Then, at time t16, the HPD transmission unit 118 maintains the HPD signal in the Low state for a period of, for example, 100 msec with respect to the HPD line 120 (step S12 in FIG. 3).

  At time t17 when 100 msec elapses from time t16, the High state HPD signal is transmitted to the HPD line 120 by the HPD transmission unit 118 (step S2 in FIG. 3). EDID access is requested from the external device 102 to the television receiver 100 in response to the High state HPD signal. In response to this request, EDID is transmitted from the television receiver 100 to the externally connected device 102 (time t18, step S3 and step S4 in FIG. 3).

  Further, a key selection vector is transmitted from the external device 102 and received by the television receiver 100 at time t19 (step S5 in FIG. 3). At time t19, as illustrated in FIG. 3E, the HDMI port selected by the selector 107 has already been changed from the HDMI port 103 to the HDMI port 104. Therefore, it is determined that the port corresponding to the external device 102 has been selected (step S6 in FIG. 3), and it is determined that the HDCP authentication has succeeded at time t20 (step S7 in FIG. 3). When the authentication by HDCP is successful, video data and audio data are transmitted from the external connection device 102 to the television receiver 100.

  As described above, according to the first embodiment of the present invention, the externally connected device can access the EDID ROM, but can stably input even when the DDC line is in an indefinite state that the HDCP ROM cannot be accessed. Switching can be done. As a result, the video data and audio data from the externally connected device cannot be displayed on the television receiver 100, and the reliability of the system is improved. In addition, when input switching is executed when the DDC line is indefinite, it is not necessary to monitor video data and audio data, and therefore it is possible to shorten the time required for monitoring to detect an abnormality.

<Second Embodiment>
Next, processing according to the second embodiment of the present invention will be described with reference to the flowchart of FIG. 5, the timing chart of FIG. 6, and the block diagram of FIG. 2 described above. FIG. 5 is a flowchart showing an example of processing according to the second embodiment of the present invention.

  In the second embodiment, in response to the transmission of the final data of EDID to the external connection device, it is determined whether the selector 107 has selected the HDMI port corresponding to the external connection device. If it is determined that the selector 107 has not selected the HDMI port, a Low state HPD signal is transmitted to the externally connected device, and the selector 107 waits for the HDMI port to be selected.

  Here, a case where the external connection device 102 is selected from the external connection device 101 connected to the HDMI port 103 and the external connection device 102 connected to the HDMI port 104 will be described as an example. Of course, the processing described below is the same even if the externally connected device 102 and the externally connected device 101 are interchanged.

  In the following description of the second embodiment, the description of the parts common to the first embodiment described above will be omitted as appropriate.

  In step S20, the control unit 112 waits for a DDC access request from the externally connected device 102. If it is determined that there is a DDC access request from the externally connected device 102, the control unit 112 shifts the processing to step S21. In step S <b> 21, the HPD transmission unit 118 transmits a High state HPD signal to the HPD line 120 to notify the externally connected device 102 that the DDC access has been turned on.

  In the next step S22, an EDID request from the external device 102 is waited. When a slave address and a read command are supplied from the external device 102 to the EDID ROM 106 via the DDC line 123, the EDID is read from the EDID ROM 106 and transmitted to the external device 102 (step S23). .

  In the next step S24, the control unit 112 determines whether or not the final data of EDID has been transmitted. That is, the EDID final determination unit 121 in the control unit 112 monitors the DDC line 123 and determines whether the transmitted EDID is the final data of EDID. For example, if the data transmitted to the DDC line 123 is the 256th byte data in the EDID, the EDID final determination unit 121 determines that the final data has been transmitted. If the EDID final determination unit 121 determines that the final data has been transmitted, the process proceeds to step S25.

  In step S <b> 25, the selector determination unit 113 determines whether the selector 107 selects a port corresponding to the external device 102 (the HDMI port 104 in this example) among the HDMI ports 103 and 104. Based on the determination result, the HDMI port selected by the selector 107 is detected. As a result, if the selector 107 determines that the HDMI port 104 corresponding to the externally connected device 102 is selected, authentication processing by HDCP is performed.

  That is, the external connection device 102 accesses the HDCP ROM 109 connected to the HDMI receiver 108 via the DDC line 123 and the selection input terminal 107B of the selector 107. Then, the external connection device 102 reads the authentication information stored in the HDCP ROM 109 via the DDC line 123 and authenticates the television receiver 100.

  If the authentication by HDCP is successful (step S26), the externally connected device 102 outputs video data and audio data. The video data and audio data are received by the television receiver 100 (step S27). In the television receiver 100, the video data and audio data are received by the HDMI port 104 and supplied to the HDMI receiver 108 via the selection input terminal 107 </ b> B of the selector 107. The HDMI receiver 108 decrypts the supplied video data and audio data, supplies the video data to the video processing unit 110, and supplies the audio data to the audio processing unit 111 (step S28).

  On the other hand, if it is determined in step S25 described above that the selector 107 does not select the HDMI port 104 corresponding to the external device 102, the process proceeds to step S29. In step S <b> 29, the HPD transmission unit 118 transmits a Low state HPD signal to the external device 102. Thereafter, the process proceeds to step S30 and waits for the selector 107 to select the HDMI port 104 corresponding to the external device 102.

  For example, in step S30, if the control unit 112 detects that the selector 107 has changed the selection from the HDMI port 103 to the HDMI port 104 based on the determination result of the selector determination unit 113, the process returns to step S21. Then, the HPD transmission unit 118 switches the HPD signal transmitted to the external device 102 from the Low state to the High state. As a result, the external connection device 102 is notified again that preparation for DDC access has been completed, and EDID request processing and HDCP authentication processing are performed again.

  The process according to the second embodiment will be described more specifically with reference to the flowchart of FIG. 5 as appropriate while using the timing chart of FIG. In FIG. 6, FIGS. 6A to 6D show various signals on the external device 101 side, that is, the HDMI port 103 side, as in FIGS. 4A to 4D described above. An example of timing is shown. 6 (f) to 6 (i) are examples of timings of various signals on the external device 102 side, that is, the HDMI port 104 side, as in FIGS. 4 (f) to 4 (i) described above. Show. Further, FIG. 6E shows an operation timing of an example of the selector 107, as in FIG. 4E described above.

  As an example, a case where the external connection device 101 is connected to the HDMI port 103 from the beginning and the HDMI port 103 is selected in the selector 107 will be described. In this case, for example, a predetermined voltage is applied to the 5V Power line 116 with the activation of the external connection device 101 (time t30 in FIG. 6). The 5V Power determination unit 115 determines that there is a DDC access request from the external device 101 based on the voltage value of the 5V Power line 116 (step S20 in FIG. 5).

  In response to the DDC access request, the HPD transmission unit 118 sets the HPD signal to the high state at time t31 (step S21 in FIG. 5). Thereafter, an access request for the EDID ROM 105 is transmitted from the external device 101 to the television receiver 100. Then, the EDID read from the EDID ROM 105 by this access request is transmitted to the external device 101 at time t32 (step S22 and step S23 in FIG. 5).

  If the EDID final determination unit 121 determines that the final data of EDID has been transmitted (step S24 in FIG. 5), the process proceeds to step S25. In step S25, based on the determination result of the selector determination unit 113, the HDMI port selected by the selector 107 is detected, and it is determined whether the selector 107 selects the HDMI port 103 corresponding to the external device 101.

  In the third example, the external connection device 101 is connected to the HDMI port 103 and the selector 107 selects the HDMI port 103 corresponding to the HDMI port 103 as illustrated in FIG. Yes. Therefore, the external device 101 can access the HDCP ROM 109 (time t33), and the HDCP authentication is successful (step S26 in FIG. 5). Thereby, at time t34, video data and audio data are output from the external device 101 to the television receiver 100 (step S27 in FIG. 5).

  As another example, a case will be described in which the input is switched to the HDMI port 104 to which the external connection device 102 is connected in a state where the HDMI port 103 to which the external connection device 101 is connected is selected as an input as in the above example. .

  For example, when a predetermined voltage is applied to the 5VPower line 117 with the activation of the externally connected device 102 (time t40 in FIG. 6), the 5VPower determining unit 115 determines that a DDC access request has been received from the externally connected device 102. (Step S20 in FIG. 5).

  In response to the DDC access request, the HPD transmission unit 118 sets the HPD signal to the High state at time t41 (step S21 in FIG. 5). Thereafter, an access request to the EDID ROM 106 is transmitted from the external device 102 to the television receiver 100. The EDID read from the EDID ROM 106 by this access request is transmitted to the external device 102 at time t42 (steps S22 and S23 in FIG. 5).

  If it is determined by the EDID final determination unit 121 that the final data of EDID has been transmitted (time t43), the selector 107 detects whether or not the HDMI port 104 corresponding to the external device 102 is selected. As illustrated in FIG. 6E, it is determined that the HDMI port 103 is selected at time t43 and the HDMI port 104 corresponding to the external device 102 is not selected.

  In this case, the HPD transmission unit 118 transmits an HPD signal in a low state at time t44 in accordance with the process of step S29 in FIG. Then, the selector 107 waits for the HDMI port 104 corresponding to the external device 102 to be selected. For example, when it is detected at time t45 that the selector 107 has selected the HDMI port 104 corresponding to the external device 102, the process returns to step S21 in FIG. Then, the HPD transmission unit 118 transmits a High state HPD signal to the external device 102 (time t46). As a result, the external device 102 is again notified that the DDC access preparation is completed, the communication initialization process is performed again, and the EDID request process (time t47) and the HDCP authentication process (time t48) are performed. If the authentication by HDCP is successful, video data and audio data are transmitted from the external device 102 (time t49).

  As described above, according to the second embodiment of the present invention, the external connection device can access the EDID ROM, but the time for the DDC line indefinite state that the HDCP ROM cannot be accessed is shortened. Therefore, when input switching is performed by the selector 107, the video data and audio data output from the externally connected device can be displayed on the television receiver 100 in a shorter time than the first embodiment described above. it can.

<Third Embodiment>
Next, processing according to the third embodiment of the present invention will be described with reference to the flowchart of FIG. 7, the timing chart of FIG. 8, and the block diagram of FIG. FIG. 7 is a flowchart showing an example of processing according to the third embodiment of the present invention.

  In the third embodiment, in response to reception of a key selection vector from an externally connected device, it is determined whether or not the selector 107 has selected an HDMI port corresponding to the externally connected device. If it is determined that the selector 107 has not selected the HDMI port, a Low state HPD signal is transmitted to the externally connected device, and the selector 107 waits for the HDMI port to be selected.

  Here, a case where the external connection device 102 is selected from the external connection device 101 connected to the HDMI port 103 and the external connection device 102 connected to the HDMI port 104 will be described as an example. Of course, the processing described below is the same even if the externally connected device 102 and the externally connected device 101 are interchanged.

  In the following description of the third embodiment, the description of the portions common to the first and second embodiments described above will be omitted as appropriate.

  When it is determined that there is a DDC access request from the external device 102 (step S40), the control unit 112 shifts the process to step S41, and the HPD transmission unit 118 sends an HPD signal in a high state to the HPD line 120. Send. Then, in response to an EDID request from the external connection device 102 (step S42), the EDID is read from the EDID ROM 106 and transmitted to the external connection device 102 (step S43).

  In the next step S44, the control unit 112 determines whether or not a key selection vector has been received via the DDC line 123. In other words, when the reception of EDID is completed, the external device 102 transmits a key selection vector to the television receiver 100 to start HDCP authentication. In the television receiver 100, the HDCP start determination unit 124 in the control unit 112 monitors the DDC line 123 and detects a key selection vector transmitted via the DDC line 123. If the HDCP start determination unit 124 determines that the key selection vector has been received via the DDC line 123, the control unit 112 shifts the processing to step S45.

  In step S45, based on the determination result of the selector determination unit 113, it is determined whether or not the selector 107 selects the HDMI port (in this example, the HDMI port 104) corresponding to the externally connected device 102 among the HDMI ports 103 and 104. To be judged. If the selector 107 determines that the HDMI port 104 corresponding to the externally connected device 102 is selected, authentication by HDCP is performed.

  If the authentication by HDCP is successful (step S46), the externally connected device 102 outputs video data and audio data. The video data and audio data are received by the HDMI port 104 of the television receiver 100 (step S47) and supplied to the HDMI receiver 108 via the selection input terminal 107B of the selector 107. The HDMI receiver 108 decrypts the supplied video data and audio data, supplies the video data to the video processing unit 110, and supplies the audio data to the audio processing unit 111 (step S48).

  On the other hand, if it is determined in step S45 described above that the selector 107 does not select the HDMI port 104 corresponding to the external device 102, the process proceeds to step S49. In step S <b> 49, the HPD transmission unit 118 transmits a Low state HPD signal to the external device 102. Thereafter, the process proceeds to step S50, and waits for the selector 107 to select the HDMI port 104 corresponding to the external device 102.

  For example, in step S50, when the control unit 112 detects a change of the HDMI port selected by the selector 107 from the HDMI port 103 to the HDMI port 104 based on the determination result of the selector determination unit 113, the process proceeds to step S41. Returned. Then, the HPD transmission unit 118 switches the HPD signal to be transmitted to the external device 102 from the Low state to the High state. As a result, the external connection device 102 is notified again that preparation for DDC access has been completed, and EDID request processing and HDCP authentication processing are performed again.

  The process according to the third embodiment will be described more specifically with reference to the flowchart of FIG. 7 while using the timing chart of FIG. In FIG. 8, FIGS. 8 (a) to 8 (d) show various signals on the external device 101 side, that is, the HDMI port 103 side, as in FIGS. 4 (a) to 4 (d). An example of timing is shown. 8 (f) to 8 (i) are examples of timings of various signals on the external device 102 side, that is, the HDMI port 104 side, as in FIGS. 4 (f) to 4 (i) described above. Show. Further, FIG. 8E shows the operation timing of an example of the selector 107, as in FIG. 4E described above.

  As an example, a case where the external connection device 101 is connected to the HDMI port 103 from the beginning and the HDMI port 103 is selected in the selector 107 will be described. In this case, for example, a predetermined voltage is applied to the 5V Power line 116 with the activation of the externally connected device 101 (time t60 in FIG. 8). The 5V Power determination unit 115 determines that there is a DDC access request from the external device 101 based on the voltage value of the 5V Power line 116 (step S40 in FIG. 7).

  In response to the DDC access request, the HPD transmission unit 118 sets the HPD signal to the high state at time t61 (step S41 in FIG. 7). Thereafter, an access request for the EDID ROM 105 is transmitted from the external device 101 to the television receiver 100. Then, the EDID read from the EDID ROM 105 by this access request is transmitted to the external device 101 at time t62 (steps S42 and S43 in FIG. 7).

  When the external connection device 101 completes the reading of the EDID, the external connection device 101 transmits an HDCP key selection vector to the television receiver 100. This key selection vector is received by the HDCP start determination unit 124 at time t63.

  If the HDCP start determination unit 124 determines that the key selection vector has been received from the external device 101 (step S44 in FIG. 7), the process proceeds to step S45 in FIG. Then, the selector determination unit 113 determines whether the selector 107 selects the HDMI port 103 corresponding to the external device 101. In this example, the external connection device 101 is connected to the HDMI port 103, and the HDMI port 103 is selected by the selector 107 as illustrated in FIG. Therefore, the external connection device 101 can access the HDCP ROM 109. As a result, the HDCP authentication is successful (step S46 in FIG. 7), and video data and audio data are output from the external device 101 to the television receiver 100 at time t64 (step S47 in FIG. 7). .

  As another example, a case where the input is switched to the external connection device 102 connected to the HDMI port 104 in a state where the external connection device 101 connected to the HDMI port 103 is selected as an input as in the above-described example will be described. .

  For example, when a predetermined voltage is applied to the 5VPower line 117 with the activation of the externally connected device 102 (time t70 in FIG. 8), the 5VPower determining unit 115 determines that there is a DDC access request from the externally connected device 102. (Step S40 in FIG. 7).

  In response to the DDC access request, the HPD signal is set to a high state at time t71 (step S41 in FIG. 7), and thereafter, an access request to the EDID ROM 106 is transmitted from the external connection device 102 to the television receiver 100. . The EDID read from the EDID ROM 106 by this access request is transmitted to the external device 102 at time t72 (steps S42 and S43 in FIG. 7).

  When the external connection device 102 completes the reading of the EDID, the external connection device 102 transmits a key selection vector to the television receiver 100 and attempts authentication by HDCP. The key selection vector is received by the television receiver 100 at time t73 (step S44 in FIG. 7). In the television receiver 100, when the key selection vector is received, the selector determination unit 113 determines whether or not the HDMI port 104 corresponding to the external device 102 is selected in the selector 107 (step S45 in FIG. 7). ). In the example of FIG. 8, it is determined that the HDMI port 103 is selected at time t73 and the port corresponding to the external device 102 is not selected.

  In this case, the Low state HPD signal is transmitted at time t74 in accordance with the process of step S49 of FIG. Accordingly, DDC access by the externally connected device 102 is stopped. Then, the selector 107 waits for the HDMI port 104 corresponding to the external device 102 to be selected. For example, when it is detected at time t75 that the selector 107 selects the HDMI port 104 corresponding to the external device 102 based on the determination result of the selector determination unit 113, the process returns to step S41 in FIG. Then, the HPD transmission unit 118 switches the HPD signal to be transmitted to the external device 102 from the Low state to the High state (time t76).

  As a result, the external connection device 102 is notified again that the DDC access preparation has been completed, and the EDID request processing (time t77) and the HDCP authentication processing (time t78) are performed again. If the authentication by HDCP is successful, video data and audio data are transmitted from the external device 102 (time t79).

  As described above, according to the third embodiment of the present invention, the externally connected device can access the EDID ROM, but the time for the DDC line indefinite state that the HDCP ROM cannot be accessed is shortened. Therefore, when input switching is performed by the selector 107, the video data and audio data output from the externally connected device can be displayed on the television receiver 100 in a shorter time than the first embodiment described above. it can.

  In the above description, in the television receiver 100, one of the two HDMI ports 103 and 104 is selected. However, this is not limited to this example. That is, the present invention is applicable to a case where a plurality of HDMI ports smaller than the total number of HDMI ports are selected from three or more HDMI ports. For example, even when two HDMI ports are selected from four HDMI ports and two screens of video data received by each of the selected HDMI ports are simultaneously displayed in one screen by picture-in-picture, Applicable.

  Each of the above-described embodiments can be realized by software by a computer of a system or apparatus (or CPU, MPU, etc.).

  Accordingly, the computer program itself supplied to the computer in order to realize the above-described embodiments by the computer also realizes the present invention. That is, the computer program itself for realizing the functions of the above-described embodiments is also one aspect of the present invention.

  Note that the computer program for realizing each of the above-described embodiments may be in any form as long as it can be read by a computer. For example, it can be composed of object code, a program executed by an interpreter, script data supplied to the OS, but is not limited thereto.

  The computer program for realizing each of the above-described embodiments is supplied to the computer via a storage medium or wired / wireless communication. Examples of the storage medium for supplying the program include a magnetic storage medium such as a flexible disk, a hard disk, and a magnetic tape, an optical / magneto-optical storage medium such as an MO, CD, and DVD, and a nonvolatile semiconductor memory.

  As a computer program supply method using wired / wireless communication, there is a method of using a server on a computer network. In this case, a data file (program file) that can be a computer program forming the present invention is stored in the server. The program file may be an executable format or a source code.

  Then, the program file is supplied by downloading to a client computer that has accessed the server. In this case, the program file can be divided into a plurality of segment files, and the segment files can be distributed and arranged on different servers.

  That is, a server apparatus that provides a client computer with a program file for realizing each of the above-described embodiments is also one aspect of the present invention.

  In addition, a storage medium that encrypts and stores a computer program for realizing each of the above-described embodiments is distributed, and key information for decryption is supplied to a user who satisfies a predetermined condition, and the computer has the computer. May be allowed to install. The key information can be supplied by being downloaded from a homepage via the Internet, for example.

  In addition, the computer program for realizing each of the above-described embodiments may use an OS function already running on the computer.

  Further, a part of the computer program for realizing each of the above embodiments may be configured by firmware such as an expansion board mounted on the computer, or may be executed by a CPU provided in the expansion board. Also good.

It is a basic diagram which shows roughly the system configuration | structure of an example which can apply this invention. FIG. 25 is a block diagram illustrating a configuration example of a television receiver to which the present invention is applicable. It is a flowchart which shows an example process by the 1st Embodiment of this invention. It is a time chart for demonstrating the process of an example by the 1st Embodiment of this invention. It is a flowchart which shows an example process by the 2nd Embodiment of this invention. It is a time chart for demonstrating the process of an example by the 2nd Embodiment of this invention. It is a flowchart which shows an example process by the 3rd Embodiment of this invention. It is a time chart for demonstrating the process of an example by the 2nd Embodiment of this invention.

Explanation of symbols

100 Television receivers 101 and 102 External connection devices 105 and 106 EDID ROM
107 Selector 108 HDMI Receiver 109 HDCP ROM
112 Control unit 113 Selector determination unit 115 5VPower determination unit 116, 117 5VPower line 118 HPD transmission unit 119, 120 HPD line 121 EDID final determination unit 122, 123 DDC line 124 HDCP start determination unit

Claims (7)

A plurality of connection means for connecting an external connection device, each of the plurality of connection means includes a control signal line for notifying the external connection device of the start of communication initialization processing;
Selecting means for selecting one of the plurality of connecting means as an input destination of at least one of video data and audio data;
Authentication information necessary for communication for the external connection device to output at least one of video data and audio data is stored, and accessed from the external connection device connected to the connection unit selected by the selection unit Possible storage means;
Notification means for notifying the externally connected device connected to the connection means to start the communication initialization process including access to the storage means by the control signal line included in the connection means; ,
Control means for controlling the notification by the notification means,
When the control unit detects a change in the connection unit selected by the selection unit, the control unit sets the notification unit to perform the notification through the control signal line included in the connection unit newly selected by the change. A video control device characterized by controlling. The video control apparatus according to claim 1, wherein the notification unit performs the notification by maintaining the potential of the control signal line at an off level for a predetermined time and then switching to an on level. The video control apparatus according to claim 2, wherein the predetermined time is longer than a time during which the external device can recognize the off level. It further has device information storage means for storing information related to the video control device,
The control means includes
If it is determined that the data transmitted from the device information storage means in response to a request from the externally connected device is the final data of the information, the state of the selection means is detected,
When the change of the connection means selected by the selection means is detected, the notification means is controlled to perform the notification by the control signal line included in the connection means newly selected by the change. The video control apparatus according to claim 1. The control means includes
Detecting the state of the selection means when access to the storage means is requested from the external device,
When the change of the connection means selected by the selection means is detected, the notification means is controlled to perform the notification by the control signal line included in the connection means newly selected by the change. The video control apparatus according to claim 1. Of the plurality of connection means each including a control signal line for connecting the externally connected device and notifying the externally connected device of the start of the communication initialization process, at least one of the video data and the audio data A selection step for selecting one as the input destination;
Authentication information necessary for communication for the externally connected device to output at least one of video data and audio data is stored and accessed from the externally connected device connected to the connection means selected in the selection step Notification step for notifying the externally connected device connected to the connection means to start the communication initialization process including access to a possible storage means by the control signal line included in the connection means. When,
A control step for controlling the notification by the notification step,
When the control step detects the change of the connection means selected by the selection step, the notification step is performed so that the notification is performed by the control signal line included in the connection means newly selected by the change. A control method of a video control apparatus, characterized by controlling.   A program for causing a computer to function as the video control apparatus according to any one of claims 1 to 5.

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